Last positioning and clamping mechanism



Dec. 12, 1933, I. c. BUCKMINSTER LAST POSITIONING AND CLAMPING MECHANISM Filed June 8, 1951 3 Sheets-Sheet l VE/V TUEL 8% e.

Dec. 12, 1933. BUCKMINSTER 1,938,578

LAST POSITIONING AND CLAMPING MECHANISM Filed June 8, 1931 3 Sheets-Sheet 2 NVENTUBL. 0 9 Q W1,

Dec. 12, 1933. l. c. BUCKMINSTER 1,938,578

LAST POSITIONING AND CLAMPING MECHANISM Filed June 8, 1931 s Sheets-Sheet 3 WHIHHHHMWHH?" 130 Fig.3. '1

mmmmmm Patented Dec. 12, 1933 UNITED STATES PATENT OFFICE LAST POSITIONING AND CLAIHPING MECHANISM Application June 8, 1931.

20 Claims.

This invention relates to last positioning and clamping mechanism. As herein illustrated, the invention is embodied in a machine for operating upon lasts of the type disclosed in Letters Patent of the United States No. 1,723,301, granted August 6, 1929, upon application of A. F. Pym and which machine, in certain aspects, is similar to the machine disclosed in an application for Letters Patent of the United States Serial No. 501,345, filed by the present applicant December 10, 1930, of which the present application is a continuation in part.

The machine disclosed in said Letters Patent No. 1,723,301 was particularly designed to drill a plurality of holes in the bottom of a last and to insert in said holes a corresponding number of metallic bushings or plugs in which positioning or jig holes had previously been drilled. However, as explained in the prior application above referred to, it has been found desirable to insert solid or undrilled metallic plugs in the holes in the last and thereafter to drill smaller positioning holes in these plugs.

In each of the prior machines above referred to, a toe gage and two pairs of relatively movable side gages for engaging the bottom and side of a last were provided to locate the last in the machine. However, when machines of the character above referred to are employed for drilling positioning holes in metallic plugs, as distinguished from such holes in a wood last, a firmer and more reliable support for the last during the plug drilling operation has been found desirable.

However, according to the method of lasting explained more fully in Letters Patent of the United States No. 1,674,060, Pym, granted June 8, 1928, for Method and means for positioning lasts and their shoe materials, these holes, in the metallic plugs, are relied upon to determine accurately the position of the last and of the shoe materials with relation to the wipers and other operating instrumentalities of a lasting machine so that it is important that these holes in 1 the plugs shall have an exact and predetermined relation laterally and longitudinally with respect to the contour of the last and also angularly with respect to the bottom or" the last. Hence, it is likewise important to provide, in the ma- 7 chine by which the positioning holes in such plugs are drilled, mechanism by which the last shall be brought exactly into the appropriate relation to the drills and then held firmly in such relation during the drilling.

Accordingly, the present invention provides Serial No. 542,911

improved mechanism, operable independently of the skill or care of the operator, for locating a last accurately in predetermined position with relation to means for drilling such holes and for then firmly holding the last in such position. Thus the inventionprovides mechanism by which the last will be located and held automatically in a position determined by-a plurality of gages which engage the bottom and side of the last. In the illustrative embodiment of the invention herein set forth, this mechanism comprises gages with converging faces co-operating with a clamp for engaging the upper surface of the toe por-- tion of the last, a pin for entering the thimble hole of the last and a support in which said clamp and pin are mounted for relative movement, the support also preferably being movable about a point substantially in the bottom of the last. Such a mechanism facilitates proper engagement of the last holding mechanism with lasts of different sizes and style in whatever positions such a last assumes as it is brought automatically int-o correct position by engagement with the gages, after the operator has presented the last to the machine. To that end, preferably also, the clamp and pin are mounted for relative movement in their support in a plurality of directions longitudinally, laterally and heightwise of the last, the illustrated support being self-adjusting angularly in two directions about a point substantially in the bottom of the last.

It will be understood that the particular mechanism herein described is not limited to use for the specific purpose above set forth but is adapted for use, for example, in locating and holding a last with a shoe upon it.

Furthermore, the invention comprises also various other combinaiions and arrangements of parts, as well as particular features of construction, which will now be described in detail in connection with the accompanying drawings which illustrate a preferred embodment of the invention.

In the drawings:

Fig. 1 is a front elevation of the machine, as a whole, except that the lower right side is shown broken away;

Fig. 2 is a side elevation of the last positioning and clamping mechanism with certain parts shown in section;

Fig. 3 is a plan view of a part of the mechanism just referred to;

Fig. 4 is a plan view of the toe and side gages and of certain parts associated therewith;

Fig. 5 is a transverse sectional view on a larger scale, of a last and a front elevational view of the gages which determine its position, and

Fig. 6 is a detail view, principally in longitudinal section, of the thimble pin and associated parts.

For the purposes of the present application, it will be assumed that three holes H have been drilled in the bottom of the last L and that, as indicated at the right in Fig. 5, solid or undrilled metallic plugs P have been forced home in the holes, for example, by the use of the machine of said pending application Serial No. 501,345 or even by the use of such a machine as is shown in said prior Patent No. 1,723,301. If the last is to be used in making McKay shoes a metallic clenching plate M may have been secured to the bottom of the last.

The last is then ready for the operation of the machine of the present application which is intended to drill holes H in the clenching plate and holes H" in the plugs P, as shown at the left in Fig. 5.

As already outlined, a primary purpose of the present invention is to provide means so to locate and hold the last while such holes H are being formed that they shall be located accurately and without fail in predetermined relation to the last not only laterally and longitudinally with respect to its contour but angularly with respect to the general plane of its bottom and that they shall have a predetermined depth.

The illus 1. rated machine comprises a main frame 10 to the top of which is bolted a table 12 which carries the last positioning and clamping devices to which the present invention particularly relates. These devices, like the corresponding devices in the prior machines above referred to, include a toe gage 14 secured to the table 12 and provided not only with an approximately horizontal surface 16 to engage the bottom of the last L, or more precisely the clenching plate M thereof, closely adjacent to the toe but also with a surface 18 somewhat inclined to the vertical, to engage the toe end of the last. Co-operating with this toe gage are two pairs of movable side gages in the form of levers and also having last engaging surfaces 19 somewhat inclined to the vertical, the two gages of each pair being interconnected to move simultaneously toward or from the longitudinal axis of the last. The gages 20 of one pair, pivoted at 22, engage the side of the last near its toe end, whereas the other pair 24, pivoted at 26, engage the side of the last at a greater distance from the toe gage and also have approximately horizontal surfaces 28 to engage the bottom of the last, as shown in Figs. 4 and 5. These side gages are normally spring pressed inwardly to predetermined positions where their ends are at distances apart somewhat less than the corresponding widths of the lasts to be operated upon. Moreover, all five gages, as shown in Figs, 2 and 5, are relatively high and their inclined faces converge downwarfly so that when the last is held by the operator with its bottom some distance from the surfaces 16 and 28 and is moved first inwardly and then downwardly by him, its toe end and side near its bottom will be brought into contact with and will be carried downwardly along all five of these inclined surfaces until its bottom is brought into firm contact with the three surfaces 16, 28. Thus the last automatically centers itself and is brought automatically into a predetermined position in the machine angularly, longitudinally and transversely.

Two of the side gages are provided with upward extensions, 30, 32, into contact with which on side of the last may be brought by the operator when he first places the last in the machine.

The mechanism for moving the two pairs of side gages may be, and preferably is, substantially like that fully shown and described in said prior Patent No. 1,723,301 or the similar mechanism of the said pending application.

Furthermore, as in the machine of said pending application, two members are provided for engaging the upper surface of the last and for clamping it in the position determined by the gages just described. One of these members is a block 34 (Fig. 2) to which may be secured a protective or frictional sheet 36 of leather or the like, the block being fixed to the lower end of a rod 38 which is mounted for partial rotation in bearings in a holder 40 provided on opposite sides with flat bearing surfaces 42 which have a sliding fit between two arms 44 projecting forwardly from a bracket 46 bolted to a bar 48 which forms a part of the frame 56, of the upper part of the machine, which is bolted to the table 12.

The holder 46 is provided with an enlarged head 54 which has an upper arcuate surface 56 the axis of which is located at a point C (Figs. 2 and 4) corresponding approximately to that point in the bottom of the last which is at the middle of a line drawn from the center of the surface 16 to the middle of a line joining the centers of surfaces 26. This head 54 has lateral extensions 57 (Figs. 1 and 2) which, on their under side, are provided with bearing surfaces 58 also arcute in shape and having the same axis C. These surfaces 58 slide along corresponding surfaces on inturned flanges 59 of retaining plates 60 screwed to the sides of a block 62 which at its under side has an arcuate bearing surrace 64 having the same axis C. Lugs 66 extend upward from the block 62, being pivoted on a transverse horizontal pin 68 to a block '70 having a lateral arm 72. A rod 74 extends upwardly from and is fixed to block '70 and is splined for vertical, but not rotary, movement in the frame 50. The rod 74 is provided with a double pitch screw thread 76 which is threaded into a long sleeve '77 having a ball thrust bearing 78 at its upper end. A coil spring '19 is provided to counterbalance to a considerable extent the weight of rod '74 and parts connected therewith. Fixed to this sleeve is a bevel gear 80 which is rotated by a bevel gear 81 and operating mechanism, including a treadle 82, of the character fully described in the prior machines above referred to. Fixed to and extending rearwardly and downwardly from block 62 is an arm 83. A spring 84 tends to swing this arm toward bracket 46 and to hold the toe of the last against surface 18. An adjustable stop 85 mounted in bracket 46 limits such swinging movement. A spring 86 connecting holder 40 bracket 46 tends to move the holder toward the rear and, when no last is in the machine, against a cam surface 87 of a plate 88 screwed to bracket 46. As the holder 40 and parts connected therewith are being raised to their highest position, this cam surface 87 moves them angularly outwardly about point C. Three sets of rolls 89, each set being mounted in and held together by an endless chain formed of links 90, lie between the arcuate surfaces 56 and 64 and constitute a roller bearing between head 54 and'block 62. Curved guides 92 at the opposite ends of head 54 prevent kinking of the chains.

Arranged to enter the thimble hole T of the last L is a sectional spring pin 94 (Fig. 6) screwed at its upper end into a lever 96 and having a shoulder 97 to engage the top surface of the cone or heel part of the last. The lower free ends of the sections which make up this spring pin are shaped on their inside faces to co-operate with a conical head 98 of a plunger 99 having an upwardly extending rod 160 slidable in a hole 102 in the lower end of a rod 104 pivoted at 106 in a block 108. Fastened to and connecting the plunger 99 and the rod 104 is a heavy coil spring 110. The lever 96 is pivoted at 112 to the block 108 which has an extension 114 to which is connected a spring 116 tending constantly to move the lever 96 to the position shown in Fig. 6 but permitting movement of that lever in a clockwise direction about the pivot 112. The coils of spring 110 are in contact with each other when the parts occupy the relative positions shown in Fig. 6, with the free or right end of lever 96 in its highest position and with the sections of pin 94 contracted. However, after the last has been slipping over the pin and turned clockwise, lever 96 likewise will be turned clockwise about pivot 112, as shown in Fig. 2, thus tending to move the head 98 of plunger 99 away from its pivot 106 and thereby putting spring 110 under tension and expanding the sections of pin 94 so that they firmly grip the inner wall of the thimble hole T and frictionally retain the top of the cone of the last against shoulder 97.

The block 108 is pivoted at 118 to a head 119 at the lower end of a rod 120 but with sufficient clearance between the parts to permit a slight oscillation laterally (parallel to the plane of the paper, as shown in Fig. 1),. Springs 122 on opposite sides of the pivot 118 (Figs. 2 and 6) tend to hold the block 108 and the pin 94 yieldingly in centralized position laterally. The rod 120 is slidable vertically in a sleeve 124 having lateral extensions 126 (Fig. 3) extending into a guideway 127 in a plate 128, the inner end of which has a boss 180 fitting the rod 38 so that the sleeve and parts associated therewith can he slid inwardly and outwardly along the guideway. The rod 120 is provided with a slot 132 into which extends a pin 134 to prevent turning of the rod in the sleeve 124. The plate 128 also has a downward extension 136 and a boss 138 surrounding and pinned to the rod 38. Forming the upper part of the guidewa y for the extensions 126 are two plates 140 screwed to the plate 128. The plates 140 have ratchet teeth 142which are engaged by a spring pressed bell crank lever 144, functioning as a latch and pivoted at 146 to the sleeve. This latch, when in operative position, shown in Fig. 2, looks sleeve 124 againstoutward movement along guideway 127 but permits inward movement thereof. v

The rod 120 has a fiat surface 149 on one side (Fig. 3) which co-operates with two rolls 150, 151

(Fig. 1) mounted respectively on two spring pressed bell crank levers 152, 153 pivoted respectively at 154, 155 so as to lock the rod against movement either upwardly or downwardly in sleeve 124. However, the operator may release these two rolls by pressing the outer ends of the levers 152, 153 inwardly. A collar 156 clamped near the upper end of the rod 120 prevents rod 120 from dropping through sleeve 124 when roll 150 is released. y

In the different positions of sleeve 124 along guideway 127, the rod 120 is directly below some part of a large plate 157 secured tothe lower end of a rod 158, one side of which is provided with ratchet teeth 159, the rod being slidable approximately vertically in a boss 160 at the forward end of the arm 72. v A bell crank lever 162 having one end formed as a pawl and pivoted at 163 to the boss 160 is held normally with the pawl in engagement with the ratchet teeth 159 by a spring 164 but is moved out of engagement therewith when the lever contacts with an adjustable stop 166, the rod 158 being returned to its highest position during the final part of the upward movement of shaft 74, through the action of a coil spring 168 surroundingit. The operator may depress the rod 158 to bring the plate 157 into engagement with rod 120 by pressing downwardly with his hand on the knob 170.

As in the machine of said pending application, anexhaust pipe 172 may be provided for withdrawing from the machine the chips produced by the drills, which form the positioning holes H" in plugs P, the three drills being shown at 174 in Figs. 2 and 4. The mannerof mounting and operating these drills forms no part of the present invention but may be similar to that fully explained in connection with the prior machines above mentioned. With the particular arrangement of the drills illustrated the axis of the inmost drill passes through the point C hereinbefore referred to.

e The manner in which the mechanism for positioning and holding the last L in the machine may be operated has been indicated in connection with the foregoing description of the parts thereof but it may be summarized as follows:

The last L, when presented to the machine, will have three solid or undrilled metallic plugs P set in holes in its bottom covered by clenching plate M, as shown at the right in Fig. 5. The block 34 and the thimble pin 94 will be in their uppermost position, the pawl 162 being released. The operator then places the thimble hole T over the pin 94, the cone of the last being pressedfirmly against the shoulder 97 of the pin. The last is turned clockwise about pivot 112 so that the sectional pin 94 is expanded and the last is held firmly by the pin and the upper surface of the toe portion of the last is brought beneath the block 34, 36. The operator then swings the side of the last against extensions 30, 32 and pushes the sleeve 124 inwardly to carry the toe-end of the last under block 34, 36 against the upper portion of the inclined surface 18 of the toe gage 14, when the sleeve 124 is locked to plate 128 by latch 144. The bottom of the last will still be located a considerable distance above the substantially horizom tal surfaces 16, 28 of gages-14 and 24 and then the operator, without further use of his hands and by depressing treadle .82, as in the prior machines above-referred to, rotates gear 81, thus'lowering block 34, 36, rod 120, plate 128, and connected parts. Thetoe end of the last slides down the inclined surface 18 and the inclined surfaces of the side gages 20,24 automatically turn and laterally shift the last, if necessary, as it is depressed and until it is finally'seated firmly on all three horizontal surfaces 16, 28 with the toe of the last against the lower portion of the inclined surface 18 of the toe gage and with the side of the last against the lower portions of the inclined surfaces on the side gages.

During this movement of the last the thimble pin has been free to adjust itself about the pivots 112, 118, the plate 128 may swing in a horizontal plane about the axis of rod 38, and holder 40 with plate 128 may swing about fulcrum 68 and about point C in a vertical plane.

Then, the operator by pressing downwardly on the knob 170 brings the plate 157 into contact with the upper end of rod 120 and, the pawl 162 having been moved away from. the stop 166, it holds the rods 158 and 120 firmly in depressed position. The rod '74 is held locked against vertical movement by its operating mechanism, the operator keeping the treadle 82 depressed.-

Thus the last L, after its positionhas been positively predetermined, is securely held in that position while the holes H" are being formed during the upward movement of the drills 174. Inasmuch as the block 34, 36 engages a portion of the last which is inclined to the horizontal, the force exerted in drilling the holes tends to move the last not only heightwise but also longitudinally away from the surface 18 of the toe gage. Such movement, however, is effectively resisted by the mechanism above described.

Having thus fully disclosed my invention, what I claim as new and desire to secure by Letters Patent of the United States is:

1. Mechanism of the character described having, in combination, a toe gage, two pairs of relatively movable side gages located at substantially different distances from the toe gage for engaging the bottom and side of a last to position the last and determine the plane of the last bottom, a clamp for engaging the upper surface of the toe portion of the last, a pin for entering the thimble hole of the last, a support in which said clamp and pin are mounted for relative movement in a plurality of directions longitudinally, laterally and heightwise of the last, said support being self-adjusting angularly in two directions about axes extending through or adjacent to a point in the bottom of the last, and devices by which said clamp, pin and last may be held firmly in adjusted position relatively to said gages.

2. Mechanism of the character described having, in combination, a plurality of gages for engaging the bottom and side of a last to determine its position in all directions, means for securng the last in the position thus determined including a clamp for engaging the upper suface of the toe porton of the last, a pin for entering the thimble hole of the last, and a support in which said clamp and pin are mounted for relative movement, and which is movable about a point adjacent to the bottom of the last.

3. Mechanism of the character described having, in combination, a plurality of gages for en gaging the bottom and'side of a last, means for securing the last in predetermined position including a clamp for engaging the last, a pin for entering the thimble hole of the last, and a support in which said clamp and pin are mounted and which is movable about a point adjacent to the bottom of the last.

4. Mechanism of the character described having, in combination, a pluarlity of gages for engaging the bottom and side of a last to determine its position in all directions, power operated clamping means for securing the last in the position thus determined comprising a member for engaging the upper side of the toe portion of the last, a member for engaging the cone of the last, a pin for entering the thimble hole of the last and a support in which said members and pin are mounted to permit movement of the first-named member relatively to said pin in a plurality of directions.

5. Mechanism of the character described having, in combination, a support for engaging the bottom of the toe portion of a last at a plurality of points, a clamp for engaging the top of the last at a point opposite the area engaged by said support, a member for engaging the'last at another location, means for moving said clamp and said member toward the last support for securing the last in position including a slidable rod, and means for locking it in last-clamping position.

6*..Mechansm of the character described having, in combination, a support for the bottom of a last, last-engaging means movable toward and from said support comprising a slidable rod, means constantly tending to move the rod in a direction away from said support and said last, means for looking it against such movement, and automatic means for releasing said locking means.

'7. Mechanism of the character described having, in combination, a support for the bottom of a last, last-engaging means movable toward and from said support including a clamp for engaging the last, a pin for entering the thimble hole of the last and mounted for movement both toward and from said clamp longitudinally of the last and also heightwise of the last, and separate latches for locking the pin in last-clamping position.

' 8. Mechanism of the character described having, in combination, a support for continuously engaging the bottom of the toe portion of a last at a plurality of separated points, a clamp for engaging the top of the last at a point opposite the area engaged by said support, and a member for engaging the cone of the last and mounted for movement about a point adjacent to the bottom of the last.

9. Mechanism of the character described having, in combination, a support for engaging and supporting the botiom of the forepart of a last at three separated points at the toe and side of the forepart, a clamp for engaging the top of the last at a point opposite the area engaged by said support, a member for engaging the last at another location, a support for said clamp and member having an arcuate surface and another member having an arcuate guideway co-operating therewith.

l0. Mechanism of the character described having, in combination, a support for the bottom of a last, members for engaging the upper portion of the last respectively adjacent its toe and heel ends, a support for said members mounted for movement toward and from the first-mentioned 126 support and also movable angularly in two planes about a point adjacent to the bottom of the last.

11. In mechanism of the character described, an abutment for a last, a member having an arcuate surface and carrying said abutment, in 130 combination with another member having an arcuate surface corresponding to the first-mentioned surface and a series of rollers connected by links to constitute an endless chain interposed between said surfaces with one run of the chain extending across radii between said surface and its axis and means for retaining said parts in assembled relation.

12. Mechanism of the character described having, in combination, a support for the bottom of a last, a clamp for engaging the upper surface of the toe portion of the last, a pin for entering the thimble hole of the last, and a support in which said clamp and pin are mounted,

said support being movable in two directions relatively movable side gages for engaging the bottom and side of a last, gages having their surfaces which engage the side of the last converging, means for engagi g the upper portion of te last, leans for orting said members for relative mover in a piuality of directions, means by which said members and their supporting means first be moved to carry last along converging surfaces to bring its bottom to engagement with said gages and then be he :l firmly in such position.

14. Mechanism of the described having, in combination, a pl of relatively movable gages having conve faces to engage the side of a last and o faces to engage its bottom, o her members for engaging the last including a pin for entering its thimble hole, said members being mounted for relative movement in a pi ality of ns, and means by which said members may be moved to carry the last along said converging surfaces to bring its bottom into enga nt with said gages.

c character described, hole of a last and is mounted for longii being -ounted for a ons,in comame laterally and cor loc" it against a pin for en a rod on w idinal mo e 16. In niechai' or a sectional pin for enter 1 a last, means :fexpanding lly and yieldingly in combination w for the pin and connections between said pin and its support permitting angular movement of the pin on the support in two different planes.

hole

17. In mechanism of the character described, a sectional pin for entering the thimble hole of a last, a lever in which said pin is mounted, a. support to which the lever is pivoted, in combination with a plunger offset from the fulcrum of the lever and having a conical head, a spring connecting said plunger and said support and constructed and arranged to cause said head to expand the sections of the pin radially as the lever is moved about its fulcrum.

18. In mechanism of the character described, a sectional pin, a lever in which said pin is mounted, a support to which the lever is pivoted, in combination with a member for expanding said pin, and means connecting said support and said member and constructed and arranged to expand the sections of the pin radially as the lever is moved about its fulcrum.

13. In mechanism of the character described, a sectional pin, a support therefor, a member for expanding said pin, and means connecting said support and said member constructed and arranged to expand the sections of the pin radially as it is moved relatively to said support.

20. In mechanism of the char cter described, a sectional pin, a lever in Which the pin is mounted, means including a spring for causing the sections of the pin to expand radially as the lever is moved about its fulcrum in one direction and another spring tending to turn the lever in the opposite direction about its fulcrum into a position where the sectional pin is contracted.

CERrIrICA'iE 0F CORRECTION.

Patent No. 1,938,578. December 12, 1933.

IRA G. BUGKMINSTER.

it is hereby certified that error appears in the printed specification of the above numbered patent requiring correction as follows: Page 5, line 3, claim 13, for "means" read members; and that the said Letters Patent should be read with this correction therein that the same may conform to the record of the case in the Patent Office.

Signed and sealed this 13th day of March, A. D. 1934,

F. M. Hopkins (Seal) Acting Commissioner of Patents. 

